Darn, that is one nice museum quality SKS!
Back in the 80's when I saw my first non bring back or over yonder SKS I was range officer on a small rifle range that had a nice concrete pad with stable tables and a nice roof of corrigated "tin" over plywood with 4x4s providing support.
I walked behind the shooter as he fired his first shot. As he checked his spotting scope his buddy was looking around for the ejected case. I commented that they sometimes ejected straight up so it could have bounced anywhere. For whatever reason I glanced up and there was the spent case, sticking mouth first into one of the 4X4 cross beams.
Right away I knew I had to have a rifle that provided its own AA coverage while firing at targets down on the ground!
-kBob